The frequency of endoscopic complications is likely to rise owing to the increased number of indications for therapeutic procedures and also to the increased complexity of endoscopic techniques. Informed patient consent should be obtained as part of the procedure. Prevention of endoscopic adverse events is based on knowledge of the relevant risk factors and their mechanisms of occurrence. Thus, suitable training of future gastroenterologists and endoscopists is required for these complex procedures. When facing a complication, appropriate management is generally provided by an early diagnosis followed by prompt therapeutic care tailored to the situation. The most common complications of diagnostic and therapeutic upper gastrointestinal endoscopy, retrograde cholangiopancreatography, small bowel endoscopy and colonoscopy are reviewed here. Different modalities of medical, endoscopic or surgical management are also considered.